Just another alternator charging, battery thread - help for new owners?

[JD4044M]

I saw those working on the Cab Latch I will look at the connections tomorrow. Maybe it needs a Voltage Regulator? For all the connections all you have to do is Bump the Start Button and it fires right off.

 

[JD4044M]

Found this Voltage Chart for 12/24 VDC Batteries at different levels of charge.

 

[Ronmar]

Yea because of the variables, the only real accurate voltage measure of a battery SOC are the conditions listed in column 1, and then only after the battery has been setting an hour or more for the electrolyte levels to stabilize in the cells...

i think you will probably find a bad connection at the polarity box...

 

[JD4044M]

I will look at those today when I get back from a day of Side Job Tractor Work so I can buy more parts! Thanks I will check my voltage on the Batteries this morning after sitting all night. I will make a note of it. Checking for current draws while off?

 

[Ronmar]

I will look at those today when I get back from a day of Side Job Tractor Work so I can buy more parts! Thanks I will check my voltage on the Batteries this morning after sitting all night. I will make a note of it. Checking for current draws while off?

There is a small vampire load from the 12v to the transmission...

here are my two battery voltages when idling... 14.23/14.42... i have a solar panel, a simple buck converter set to float the 12v batt(the one with the vampire on it) to 13.2v when the sun is out, and an equalizer that holds the two batts within 0.2v of each other. These were taken after a night of static/discharge from the vampire, before the sun was on the panel, so I suspect the 12v batt was a little more thirsty than the 24v batt. I suspect after a little runtime these would settle in a little closer to each other, but that is really splitting hairs... These are well within the traditional alternator spec of 14.5 +/- 0.5v... when I turn on the lights they increase to 14.3 and 14.5 respectively as the alt boosts output for the added load... it is also cool out which might also be contributing to a slight increase in voltage(no thermal derate)...

 

[JD4044M]

Tomorrow I get to work on the truck. Did do a hooked up Volt Lost Test on the batteries just the way there hooked up and engine off. Read the voltage 1 hour after shut down yesterday. That voltage was Front Pair 12.66 VDC, Rear Pair 12.88 VDC total 25.54 Volts. After 24 hours Front Pair 12.46 VDC(80%), Rear Pair 12.75 VDC(100%) total 25.54 VDC. So total lost on front pair 0.20 Volts and rear pair 0.13 Volts or a total of 0.33 VDC Drop for all 4 batteries total. I will inspect those connections and re/crimp them if needed. Still considered close to a full charge on them which is OK. Now to find out why charging at a lower voltage rate?

 

[Bill Nutting]

I use dielectric grease on all of my connections. It prevents oxidation and corrosion.

 

[JD4044M]

I have been using it inside and outside on the crimps plus on the Battery Posts. Great stuff been using it for years.

 

[JD4044M]

OK this is getting better all the time! I was a Journeymen Electrician in 1977 and did the trade pretty much all my life even became a Commercial Electrical Administrator. That is the hardest test of all. Just never got into Electronics which is a different trade. So I learn as I go on some things. Interesting the Diode Blocks had 2 loose Cables and a 3 needing cleaning. The Crimps were good so were the rubber covers but you could grab the cable and move it under the Nut! After cleaning and re/doing the connections in the middle of long cables the Voltage went up even more. Now all the connections are inspected/new and while running at idle The Front Pair of Batteries were at 14.50 VDC and the Rear Pair was at 17.00 VDC for 31.5 VDC Total. No real change when everything is turned on the voltage stays pretty much. My batteries are new and only lost 0.01 volts in 12 hours went down to 25.20 VDC. So still not right?? Nothing left to correct on the outside new belts too. Only leaves the expensive parts again and still so close?? Least the batteries are not going down over 2 days like before. Have not measured the Voltage running since fixing things at the Alternator, just re/did the connections on it.

 

[Ronmar]

Thats weird... What does it measure at the alt when you are getting 14.5 and 17 at the batts? That totals 31.5, and shouldn’t really be possible, unless the regulator has issues...

 

[JD4044M]

I will measure it in a few and see. Also see if things have changed any on the voltage. If Voltage Regulators were not so expensive I would just part change for a test!!

 

[JD4044M]

Ate lunch and did the test over again with the truck warmed up seems to make a difference. Before, starting the voltage was high 31.50 VDC. Shut it off waited to measure the Alternator Voltage later after lunch. Started the truck up Batteries were 13.54 VDC @ Front Pair and 13.87 VDC @ Rear Pair. Total Voltage was 27.41 VDC. At the Alternator the 12volt post was 13.57 VDC and 28volt post was 27.50 VDC all to ground. Regulator Yellow Wire = 26.62 VDC. Red Cap Wire 18.04 VDC/13.76 on AC Scale? The rest of the output posts showed only 255mv of AC on the Fluke Meter. Not sure if this is the A/C Ripple you were talking about before? So it seems things have settled in and closer to being right once more???? There is variations of a few 1/10th-1/100th a volt between readings front to rear doing them. Nothing seems to be rock solid voltage?

Need to find the Frame Ground off the batteries for the starter and 12V system forgot to check them?

 

[Ronmar]

Also check the instrument shunt conections(Under/inboard of air filter) The neg lead runs from the batts to the shunt, the other side of the shunt runs to the starter case. At that starter connection there is a ground strap that connects over to the left frame rail...

 

[JD4044M]

Picture time for me, better than my eyes looking at things. I will look for them now under he truck and Air Filter.

 

[Ronmar]

Picture time for me, better than my eyes looking at things. I will look for them now under he truck and Air Filter.

Actually the shunt is mounted right beside the polarity box(toward the rear). I am sorry, I should have mentioned it before but wasnt thinking about it...

The main Ground lead and strap run right under the starter...

 

[JD4044M]

That Block was OK I checked it at the same time. I think I found the Frame Ground Problem I was looking for. It is on the Starter Negative and the Braid going to the Frame. I will have to wipeout my neck and get to that to clean and re/do. I think this could be the charging problem? Maybe like a loose neutral on 120/240 stuff in a home voltage can go all over the place on the Legs? Anyway I am on 2 Batteries now and it starts just like it did before. Still almost there at 26.89 VDC Total and 13.73/13.16 on the 12VDC Batteries. 13.16 was the output to the 12 VDC. Switching to just 2 is easy and the other 2 now go to my Slave and set up for 24 VDC to Jump with. Need to figure a isolated charge set up. Here is the Bad Connection on the Starter and Zoom makes it look real ugly!! The Cable Hook Up is so much more cleaner and easy to follow this way.

 

[Ronmar]

Yea, that starter terminal looks pretty ugly...

 

[JD4044M]

Glad it was the Negative? It will look nicer when done. Still shinny under the nut and washers I hope. Ya looks like crap to me right now and glad I don't give up easy. Hoping this changed things to the good when corrected. Does not matter all this needed done when the batteries wiring cable connections are 26 years old and left outside.

 

[Bill Nutting]

That’s not a ground connection.... That’s a kinda ground connection. It might not be all of your problem, but it IS a problem. Nice job hunting it down!

 

[JD4044M]

Doesn't this connection connect the 12/24VDC Negative to the Starter and then the braided goes to the Frame? Course the starter is bolted to the engine to for another path. Either way seems this is a important connection to be good for a lot of reasons. Driving it to a Auction this morning to see how people react to it. Not being sold there just a lot of people know me and not seen the truck yet.